The present invention relates to a new and improved method of detecting so-called pre-magnetization or magnetization of a magnetic circuit, in particular for the detection of a current flow interlinked with the magnetic circuit. The invention further relates to apparatus for the performance of such method.
Magnetic circuits, generally in the form of highly permeable and especially ferromagnetic cores, are suitable for the detection of magnetic fields by virtue of the magnetization present in the magnetic circuit, which magnetization, in the description to follow, for the purpose of differentiating from an additionally induced detection magnetization for producing required detection signals, may be sometimes referred herein to as "pre-magnetization", but for simplicities sake is usually referred to hereinafter as simply "magnetization". When such pre-magnetization or magnetization corresponds to a current flow interlinked with the magnetic circuit, then there is produced a current detection, especially, for instance, a null current detection.